Graphical applications executed on this type of system can be developed in various programming languages and in particular in an object-oriented programming language such as Java.
In object-oriented programming, classes are defined which each have their own characteristics. The classes are related by parent-child relationships, the child class inheriting characteristics from the class of its parent.
Most graphical applications developed in the Java environment define classes representing graphical elements or components that can be nested. Examples of graphical components are: windows, input fields, “OK” buttons, labels, etc. The programmer can also define new components.
FIG. 1a) shows one example of a screen E composed in this way. The screen E includes simple graphical components such as input fields, labels, and buttons. It also includes a component (container) C that is complex, i.e. one in which components are nested. A window-type graphical component “Window 1” has been chosen first. Three components are nested in the “Window 1” component: an input field “Input 1”, an “OK” button and a container C in which are nested an input field “Input 2” and a label “Label 1”.
FIG. 1b) shows a tree of graphical components which corresponds to the above composition. The parent graphical component “WINDOW 1” has three child graphical components “INPUT 1”, “OK” and a container C, the last of which itself has two child components “INPUT 2” and “LABEL 1”.
It is useful for the user of this kind of system to be provided with keyboard shortcuts. A keyboard shortcut consists of a key which, when pressed, or a combination of keys which, when pressed simultaneously, initiate a specific action regardless of the graphical component on which it is located. For example, the keyboard shortcut “Ctrl Z” entails pressing the “Ctrl” key and the “Z” key simultaneously. Thus in this example the user may require a keyboard shortcut to initiate the action “Go back to the previous screen” when the component that is active, i.e. awaiting a keyboard event, is the “INPUT 2” component. The user would also wish to have access to the same keyboard shortcut, initiating the same action, if the active component were the “OK” button.
However, the navigation processes of graphical applications developed in Java do not provide for the use of keyboard shortcuts.